abstract |
A method is proposed for the preparation of a laminate with improved mechanical strength such as the cloth-to-cloth adhesive bonding strength using a prepreg based on a fabric sheet of aromatic polyamide fibers and an adhesive preferably selected from polyimide-based and epoxy resin-based adhesives, in which the fabric sheet is pretreated by exposure to low-temperature plasma of preferably a gas mixture composed of oxygen and nitrogen under a reduced pressure of 0.5 to 20 Torr. The improvement is derived presumably from the increase in the wettability and affinity of the fibers to the adhesive as is suggested by the remarkable increase of adhesive pick-up. |